and N-[formyl(methyl)amino]salonine-B ( (20S)-20-[formyl-(methyl)amino]-3b-methoxypregna-5,16-diene; 7) have been isolated from the MeOH extract of Sarcococca saligna, along with the six known alkaloids dictyophlebine (8), epipachysamine-D (9), saracosine (10), iso-Nformylchonemorphine (11), sarcodinine (12), and alkaloid-C (13). The structures of 1 ± 7 were deduced from spectral data. Compounds 1 ± 13 demonstrated significant activity against acetyl-and butyrylcholinesterase.

Phytochemical investigation of Sarcococca saligna by extensive bioassay-guided fractionation resulted in the isolation of the pregnane-type steroidal alkaloids 1 ± 15, i.e. of the five new compounds 1 ± 5 and the ten known alkaloids 6 ± 15. The structures of the new alkaloids salignenamide C (1), salignenamide D (2), 2bhydroxyepipachysamine D (3), salignenamide E (4), and salignenamide F (5) were elucidated with the help of modern spectroscopic techniques, while the known alkaloids axillarine C (6), axillarine F (7), sarcorine (8), N 3demethylsaracodine (9), saligcinnamide (10), salignenamide A (11), vaganine A (12), axillaridine A (13), sarsalignone (14), and sarsalignenone (15) were identified by comparing their spectral data with those reported earlier. Inhibition of electric-eel acetylcholinesterase (EC 3.1.1.7) and horse-serum butyrylcholinesterase (EC 3.1.1.8) by alkaloids 1 ± 15 were investigated. These new cholinesterase inhibitors may act as potential leads in the discovery of clinically useful inhibitors for nervous-system disorders, particularly by reducing memory deficiency in Alzheimer×s disease patients by potentiating and effecting the cholinergic transmission process. These compounds were found to inhibit both enzymes in a concentration-dependent fashion with the IC 50 values ranging from 5.21 ± 227.92 mm against acetylcholinesterase and 2.18 ± 38.36 mm against butyrylcholinesterase.1. Introduction. ± As part of our ongoing investigations on medicinal plants, we have studied the chemical constituents of the genus Sarcococca. The genus belongs to the family Buxaceae with sixteen to twenty species and is predominantly distributed from Afghanistan through the Indo-Pakistan subcontinent to Central China and Sri Lanka (Ceylon) to South-East Asia and the Philippine Islands [1]. The Sarcococca plants have been used since ancient times as folk remedies for ulcers, gastric disorders, and bacterial infections [2 ± 4].Our previous work on S. saligna (D. Don. ) Muell.-Arg. has resulted in the isolation of several steroidal alkaloids [5 ± 9]. Recently, we focused our attention on the anticholinergic constituents of this plant. The aerial parts of the plant were collected, and its MeOH extract was subjected to an activity-guided fractionation by an in vitro high-throughput cholinesterase enzyme-inhibition assay. This resulted in the isolation of the five new steroidal alkaloids 1 ± 5 and the ten known steroidal alkaloids 6 ± 15. Our interest in this study was mainly to develop a better understanding of the structureactivity relationship for this new class of cholinesterase inhibitors.According to the cholinergic hypothesis, the memory impairment in the patients with senile dementia of the Alzheimer type results from a deficiency in cholinergic function in the brain [10] [11]. Hence, the most promising therapeutic strategy for activating central cholinergic functions has been the use of cholinomimetic agents. The enzyme acetylcholinesterase (AChE) has long been an attractive target for the rational drug design a...